The case against the now-defunct Knoedler gallery and its former director Ann Freedman, accused of knowingly selling inauthentic works by some of the greatest Abstract Expressionist painters, has riveted the New York art world. It has also ensnared leading art historians—many of whom gave testimony during the trial or were cited in court papers—who had been asked to give, or who were said to have given, their opinion on the works that turned out to be fakes.